Embodiments of the invention relate to an apparatus and method for supplying chemicals in a supply line. In particular, embodiments relate to an apparatus and method for providing multiple chemicals down a single supply line, including from a surface location to an underwater hydrocarbon extraction facility.
The oil and gas industry is increasingly moving towards all-electric arrangements for underwater hydrocarbon extraction facilities (for subsea controls, for example trees and actuators), allowing for an umbilical of reduced cost due to the elimination of, for example, hydraulic lines in the umbilical. A component that cannot be easily removed from the umbilical is a chemical supply line, as these are often needed throughout the life of the facility and chemicals must be supplied at a consistent rate, with one dedicated chemical supply line required for each of various chemicals.
It is an aim of the present invention to reduce the number of chemical supply lines required. This aim is achieved by using a single chemical line to send multiple chemicals, in particular in liquid form, to the underwater area in which they are needed, for example the wellhead of the hydrocarbon extraction facility.
As prior art there may be mentioned GB2480427, which discloses a storage system for chemicals on the seabed.
As further prior art there may be mentioned, EP0169723, which discloses a method of supplying a treatment liquid to different zones in a bottling plant. It shows the use of a single line for multiple chemicals. However, the treatment liquid is mixed with a carrier liquid (see FIG. 4).